title: Influence of conjugation axis on the optical and electronic properties of aryl-substituted benzobisoxazoles.
abstract: Six different 2,6-diethyl-4,8-diarylbenzo[1,2-d:4,5-d']bis(oxazoles) and four different 2,4,6,8-tetraarylbenzobisoxazoles were synthesized in two steps: a Lewis acid catalyzed orthoester cyclization followed by a Suzuki or Stille cross-coupling with various arenes. The influence of aryl group substitution and/or conjugation axis variation on the optical and electronic properties of these benzobis(oxazole) (BBO) compounds was evaluated. Structural modifications could be used to alter the HOMO, LUMO, and band gap over a range of 1.0, 0.5, and 0.5 eV, respectively. However, depending on the location and identity of the substituent, the HOMO level can be altered without significantly impacting the LUMO level. This is supported by the calculated frontier molecular orbitals. Our results indicate that the FMOs and band gaps of benzobisoxazoles can be readily modified either jointly or individually.
authors.affiliation: Department of Chemistry, Iowa State University, Ames, Iowa 50010, USA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Tlach
authors.forename: Aimée L
authors.initials: AL
authors.lastname: Tomlinson
authors.forename: Alden G
authors.initials: AG
authors.lastname: Ryno
authors.forename: Dawn D
authors.initials: DD
authors.lastname: Knoble
authors.forename: Dana L
authors.initials: DL
authors.lastname: Drochner
authors.forename: Kyle J
authors.initials: KJ
authors.lastname: Krager
authors.forename: Malika
authors.initials: M
authors.lastname: Jeffries-EL
mesh_terms: D015394:Molecular Structure; D055620:Optical Phenomena; D010080:Oxazoles / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D010080:Oxazoles